Neglect is often produced by massive strokes in the middle cerebral artery region and is variegated, so that most sufferers do not exhibit all of the syndrome's traits.

In an extreme case, a patient with neglect might fail to eat the food on the left half of their plate, even though they complain of being hungry.

[1] Neglect may also present as a delusional form, where the patient denies ownership of a limb or an entire side of the body.

[citation needed] Brain areas in the parietal and frontal lobes are associated with the deployment of attention (internally, or through eye movements, head turns or limb reaches) into contralateral space.

[7] The lack of attention to the left side of space can manifest in the visual, auditory, proprioceptive, and olfactory domains.

Hemianopsia arises from damage to the primary visual pathways cutting off the input to the cerebral hemispheres from the retinas.

[13] In this theory, neglect patients demonstrate a failure to describe the contralesional side of a familiar scene, from a given point, from memory.

[citation needed] To support this theory, evidence from Bisiach and Luzzatti's study of Piazza del Duomo can be considered.

For the study, patients with hemispatial neglect, that were also familiar with the layout of the Piazza del Duomo square, were observed.

Results showed that the majority of the eye movements were aimed to his right side, indicating that the images represented in his dreams were also affected by hemispatial neglect.

[16] Patients show a contralesional loss of space representation with a deviation of spatial reference to the ipsilesional side.

In order to assess not only the type but also the severity of neglect, doctors employ a variety of tests, most of which are carried out at the patient's bedside.

Despite such limitations, we may loosely describe unilateral neglect with four overlapping variables: type, range, axis, and orientation.

The neglect of input, or "inattention", includes ignoring contralesional sights, sounds, smells, or tactile stimuli.

[19] These patients tend to neglect the opposite side of their lesion, based on the midline of the body, head, or retina.

Sacks (1985) described a patient who fell out of bed after pushing out what he perceived to be the severed leg of a cadaver that the staff had hidden under his blanket.

That is to say, what frame of reference does a subject adopt when neglecting the left half of his or her visual, auditory, or tactile field?

To begin, one study conducted by Dongyun Li, Hans-Otto Karnath, and Christopher Rorden examined whether allocentric neglect varies with egocentric position.

[24] To test the neglect frame of reference, the two different arrays were carefully situated so that gap in the triangle fell on opposite sides of the allocentric field.

[24] A second study, conducted by Moscovitch and Behrmann, investigated the reference frame of neglect with respect to the somatosensory system.

Treatment consists of finding ways to bring the patient's attention toward the left, usually done incrementally, by going just a few degrees past midline, and progressing from there.

Forms of treatment that have been tested with variable reports of success include prismatic adaptation, where a prism lens is worn to pull the vision of the patient towards the left, constrained movement therapy where the "good" limb is constrained in a sling to encourage use of the contralesional limb.

Pharmaceutical treatments have mostly focused on dopaminergic therapies such as bromocriptine, levodopa, and amphetamines, though these tests have had mixed results, helping in some cases and accentuating hemispatial neglect in others.

Subjects received 15 consecutive treatment sessions and were evaluated on different aspects of the neglect disorder including perception of midline, and scanning deficits.

The study found that there is evidence that neck muscle stimulation may work, especially if combined with visual scanning techniques.

Of these emerging treatment options, the most studied intervention is prism adaptation and there is evidence of relatively long-term functional gains from comparatively short-term usage.

The review also suggests that Optokinetic Stimulation is effective in improving position sense, motor skills, body orientation, and perceptual neglect on a short-term basis.

A few Trunk Rotation Therapy studies suggest its effectiveness in improving performance on neglect tests as well as the Functional Independence Measure (FIM).

One such device is the Bon Saint Côme apparatus, which uses spatial exploratory tasks in combination with auditory and visual feedback mechanisms to develop trunk control.

The Bon Saint Côme device has been shown to be effective with hemiplegic subjects due to the combination of trunk stability exercises, along with the cognitive requirements needed to perform the postural tasks.